U.K. near-midairs

Mark James Boyd wrote:
+ $160/every two years,

It's more like $75-100 every two years, as a transponder in a glider
just needs VFR certification (i.e., no static leak-down test).

Marc

"Mark James Boyd" wrote in message
news:41a81fb1$1@darkstar...
Eric Greenwell wrote:
Mark James Boyd wrote:

In the US, I'm not aware of any ACTUAL midair collisions between a
glider and non-glider that are more than 4 miles from an airport.

About 15 years ago near Ephrata, Washington, there was a glider/airplane
collision about 10 miles from the airport. Everyone was killed. I don't
remember the details, or even if they were determined with any
confidence.

Can't find this one in fatals/glider/state of washington on NTSB. Hmmm...
Looked for 1980 to 1999...


I seem to recall one near Truckee 5-10 years ago, but don't remember how
far it was from the airport.

3/31/1998, Grob 102 vs. Aero Commander 690, vicinity of the airport,
all uninjured

Yes, but VERY lucky. The empennage was sort of flopping about. The landing
was not pretty.

Frank

In article , Charles
Yeates writes
BTIZ wrote:

It could be your local Halifax controllers are not trying, have to many
filters turned on.. or are just not experienced in radar operation.


It is the filter settings -- they don't want to see birds {:))

Oh. Don't they want to avoid bird strikes, then?
--
Mike Lindsay

Sometimes that is so; what if you install one because
you want to operate in Class A or B airspace [as opposed
to being more visible in uncontrolled airspace]?

Ian




At 07:30 27 November 2004, Marc Ramsey wrote:
Mark James Boyd wrote:
+ $160/every two years,

It's more like $75-100 every two years, as a transponder
in a glider
just needs VFR certification (i.e., no static leak-down
test).

Marc

In the USA there are simple and fatal flaws with any system that
includes ground based radar and a controller near a high density airport.

First, as already mentioned, the controller's normal display is
processed information. The is often referred to as secondary radar.
Basically it is just the transponder equipped traffic with data tags.

Second, as already mentioned, the system is normally configured to drop
out targets that have a low ground speed or don't have a ground track
that is going somewhere (e.g. circling). So a radar reflector wouldn't
be much help. It isn't the size of the return that gets the target
filtered out under these circumstances.

Third, and probably the greatest problem, if there are too many 12XX
returns (VFR transponder equipped traffic in the USA) the controller can
filter the specific codes or blocks of codes.

The was a mid-air between a commuter flight and a skydiving jump plane
between Denver CO and Cheyenne WY about 15 or 20 years ago. The
commuter flew into the climbing jump plane. Since they we both above
12,500 MSL (about 7,000 AGL), it was assumed the commuter pilots were
heads down in the cockpit. The jump plane was using a transponder code
of 1234 and ATC had 12XX code filtered for the higher altitudes. The
jump plane was not talking to ATC. Oops...

Other than a TCAS installation (aircraft to aircraft), the only way a
transponder will help us is if the ATC facility in the area knows about
the glider operations and can (or will) operate their equipment in a
manner that allows the controller to see the glider traffic. That means
we have to work with the local ATC folks. Otherwise, it is so much extra
ballast and power draw in the glider.

Even when the technology should help, local procedures can negate the
technology. Since the way we operate gliders does not fit in the
general transportation model the ATC system is designed to support,
putting a transponder into a glider without working with the affected
ATC organization does little to help the situation.

Dave Rolley

Mark James Boyd wrote:
BTIZ wrote:

you'd be better off stuffing in a transponder for their TCAS and for ATC to
really see you.


I think we all understand that putting in a transponder and a
big battery is a more complete solution. I think those
on this thread are simply looking at the lower tech, less expensive,
no recurrent certification alternatives.

At $50 and one pound, this looks pretty good. At $1000 and
10 pounds (including the extra battery) + $160/every two years,
I suspect we'd see fewer takers.

I personally also love the idea of the "star" multi-faceted
reflective tape. I despise the green and light grey color of
my current airplane, for example.

Cheap, passive, low cost solutions have a sort of engineering elegance,
don't you think?

--

------------+
Mark J. Boyd

Ian Cant wrote:
Sometimes that is so; what if you install one because
you want to operate in Class A or B airspace [as opposed
to being more visible in uncontrolled airspace]?

Assuming you are talking about the US, I've never seen any explicit
requirement for IFR transponder certification for entry into Class B
airspace (assuming VFR operation). As for Class A (outside of a wave
window) you would be operating IFR, so I would guess IFR certification
would be a requirement, as well as the sensible thing to do.

Marc

On Thu, 25 Nov 2004 21:15:23 UTC, "Peter Seddon"
wrote:

: The area is marked as an area
: of intense gliding activity and the airfield is marked with cables. We've
: had a couple of near thing over the airfield.

I have on several occasions seen light single engined aircraft pass
directly over the SGU site at Portmoak on their way - I presumed - to
or from Edinburgh airport. They were at 1000', or to put it another
way, 300 - 600' below the height the winches cables were getting to.

And I have I told you about the Tornado which passed me on the level,
in the Cheviots, about 2 wingspans away from me?

Ian
:


--

On Fri, 26 Nov 2004 01:37:03 UTC, Nyal Williams
wrote:

: Boating stores sell radar reflectors made of cardboard
: and covered with aluminum foil.

I have never seen a cardboard one, but I do have a light alloy one on
the boat.

: I inquired about their use in gliders (practically
: no weight and could go in fuselage behind wing) and
: someone told me they would not give a strong enough
: signal for aircraft use owing to the speeds involved.

I have heard that a military ATC who visited one site where I fly said
that it would make a considerable improvement to the radar return from
a glider. It's on my list of things to do.

Ian

On Fri, 26 Nov 2004 21:22:05 UTC, Eric Greenwell
wrote:

: This is quite variable, depending on the radar and the operator, but if
: you present a bigger primary return, your chances are improved.

Absolutely. No one ever became less visible with a radar reflector...

Ian
--

I have on several occasions seen light single engined aircraft pass
directly over the SGU site at Portmoak on their way - I presumed - to
or from Edinburgh airport. They were at 1000', or to put it another
way, 300 - 600' below the height the winches cables were getting to.

And I have I told you about the Tornado which passed me on the level,
in the Cheviots, about 2 wingspans away from me?

Ian
:


I've had a few good flight at SGU, I must say that I've been too bussy
looking out for other gliders buzzing up and down Bishop to see anything in
the far distance. It gets hectic up there, and Perth airport is not too far
away with quite a lot of GA going on.

Peter.